Poster Presentation & Flash Talk 46th Annual Meeting of the Fetal and Neonatal Physiological Society 2019

When does prone sleeping improve cardiorespiratory status in preterm infants in the NICU? (#111)

Kelsee Shepherd 1 , Stephanie Yiallourou 1 2 , Sasha Odoi 1 , Emma Yeomans 3 , Rosemary Horne 1 , Flora Wong 1 3
  1. Monash University/ Hudson Institute of Medical Research, Clayton, VICTORIA, Australia
  2. Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
  3. Monash Newborn, Monash Children's Hospital, Clayton, Victoria, Australia

Preterm infants in NICU are often placed prone to improve respiratory function. Clinical guidelines recommend preterm infants are slept supine from 32 weeks of postmenstrual age (PMA), regardless of gestational age (GA) at birth. However, respiratory dysfunction is related to GA and chronological age after birth rather than PMA. Respiratory function is also affected by the sleep state. We assessed the effects of position and sleep state on cardiorespiratory events in preterm infants longitudinally, in relation to GA at birth and PMA.

Twenty-three extremely (24-28 weeks’ GA) and 33 very preterm (29-34 weeks’ GA) infants were studied weekly from birth until discharge, in prone and supine positions, and in quiet sleep (QS) and active sleep (AS). Cardiorespiratory events were defined as bradycardia (heart rate≤100 bpm) and desaturations (oxygen saturation ≤80%). Frequency and duration of the cardiorespiratory events were analysed. Percentages of time spent in each sleep states (QS% and AS%) were quantified.

In extremely preterm, the prone position reduced the frequency of bradycardias and desaturations, and desaturation duration. The %QS was higher in prone compared to supine position. In contrast, in very preterm infants, prone positioning only reduced frequency of desaturations. In very preterm infants, prone positioning increased %QS and reduced %AS compared to supine positioning. The position-related effects in both groups of infants were not related to PMA or chronological age. QS reduced bradycardias and desaturations in both extremely and very preterm infants. In the extremely preterm infants only, cardiorespiratory events reduced with increasing PMA rather than chronological age.

Prone-position-related benefits in cardiorespiratory function are dependent on GA but not PMA. Cardiorespiratory stability was improved by the prone position only in extremely preterm infants, with minimal effects in very preterm infants from PMA of 30 weeks onwards. This evidence should be considered in future recommendations for preterm infant positioning.